Rearranged iridal-type triterpenoids from Iris tectorum.

Three new iridal-type triterpenoids (1-3) featuring a rearranged homofarnesylside chain were isolated from the rhizomes of Iris tectorum. Compounds 2 and 3 were found to be a pair of epimers. Their structures were elucidated on the basis of comprehensive spectroscopic analysis. A possible biosynthetic pathway for them was postulated. Moreover, the mixture of compounds 2 and 3 exhibited moderate neuroprotective activity against serum deprivation-induced PC12 cell death.

A Chemical Investigation of the Leaves of Morus alba L.

The leaves of Morus alba L. are an important herbal medicine in Asia. The systematic isolation of the metabolites of the leaves of Morus alba L. was achieved using a combination of liquid chromatography techniques. The structures were elucidated by spectroscopic data analysis and the absolute configuration was determined based on electronic circular dichroism (ECD) spectroscopic data and hydrolysis experiments. Their biological activity was evaluated using different biological assays, such as the assessment of their capacity to inhibit the aldose reductase enzyme; the determination of their cytotoxic activity and the evaluation of their neuroprotective effects against the deprivation of serum or against the presence of nicouline. Chemical investigation of the leaves of Morus alba L. resulted in four new structures 1⁻4 and a known molecule 5. Compounds 2 and 5 inhibited aldose reductase with IC50 values of 4.33 µM and 6.0 µM compared with the potent AR inhibitor epalrestat (IC50 1.88 × 10−3 µM). Pretreatment with compound 3 decreased PC12 cell apoptosis subsequent serum deprivation condition and pretreatment with compound 5 decreased nicouline-induced PC12 cell apoptosis as compared with control cells (p < 0.001).

Heliosterpenoids A and B, two Novel Jatrophane-Derived Diterpenoids with a 5/6/4/6 Ring System from Euphorbia helioscopia.

Heliosterpenoids A and B (1 and 2), two unprecedented jatrophane-derived diterpenoid esters with a novel 5/6/4/6-fused tetracyclic ring skeleton, were isolated from the whole plants of Euphorbia helioscopia. The structures of 1 and 2 were elucidated by extensive spectroscopic methods and electronic circular dichroism (ECD) analyses. The plausible biogenetic pathways of 1 and 2 were postulated. 1 and 2 were found to be potent inhibitors of P-glycoprotein (ABCB1) and 1 also exhibited cytotoxicity against MDA-MB-231 cell lines.

Aristolochic acid derivatives from the rhizome of Arisolochia championii.

Four new aristolochic acid derivatives aristchamic A (1), aristchamic B (2), aristochamic C (3a), aristchamic D (3b) and one new aristolactam aristolactam-CV (4), together with 10 known compounds (5-14), were isolated from the rhizomes of Aristolochia championii. Their structures were assigned by detailed analysis of MS and NMR spectroscopic data. All of the isolated compounds were evaluated for their cytotoxic activities against HCT-116, HepG2, BGC-823, NCI-H1650, and A2780 cell. Compound 1 exhibited significant cytotoxic activity against HCT-116, HepG2, BGC-823, and NCI-H1650, with IC50 values of 0.50, 7.37, 2.66, and 0.75µM, respectively.

Three new triterpenoids from Ganoderma theaecolum.

Three new triterpenoids (1-3), together with four known triterpenoids (4-7), were isolated from the fruiting bodies of Ganoderma theaecolum. Their structures were elucidated on the basis of their spectroscopic data and chemical evidence. Compounds 4 and 6 exhibited antitumor activities against H460 cells with IC50 values of 22.4 and 43.1 µM, respectively. And the cytotoxic activities of compounds 4 and 5 against MDA-MB-231 cancer cell lines were assayed with IC50 values of 49.1 and 75.8 µM, respectively.

Apocynin derivatives from Iris tectorum.

Phytochemical investigation of the rhizomes of Iris tectorum resulted in the isolation and characterization of three new apocynin derivatives, apocynin-4-O-ß-D-(6'-O-syringyl)glucopyranoside (1), scrophenoside C-7-ethyl ether (2, 3), together with a new naturally occurring compound but known by synthesis, apocynin-4-O-ß-D-xylopyranoside (4), and five known ones (5-9). Their structures were elucidated on the basis of spectroscopic data interpretation.

Polycycloiridals with a Cyclopentane Ring from Iris tectorum.

Six new iridal-type triterpenoids containing an unprecedented cyclopentane ring, polycycloiridals E-J (1-6), were isolated from a large-scale re-extraction of Iris tectorum. A possible biosynthesis pathway is postulated. The known spirioiridotectal D (7) was also obtained in the current investigation, and its structure was unequivocally defined using X-ray diffraction data. Compound 7 suppressed LPS-activated NO production in the BV2 cell line with an IC50 value of 0.54 µM.

Four new compounds from the rhizome of Aristolochia championii.

Three new flavonoid glycosides (1-3) and one new aristololactam N-glycoside (4) were isolated from the rhizome of Aristolochia championii. The structures of compounds 1-4 were elucidated on the basis of their spectroscopic data and chemical evidence (UV, IR, HR-ESI-MS, 1D and 2D NMR). Their structures were determined as 8-(5-formyl-2-furanmethyl)-isorhamentin 3-O-robinobioside (1), 8-(5-methyl-2-furanoyl)-isorhamentin 3-O-robinobioside (2), 8-formylisorhamentin 3-O-robinobioside (3), and N-ß-D-glucopyranosylaristololactam V (4), respectively.

Aromatic glycosides from the whole plants of Iris japonica.

Phytochemical investigation on the whole plants of Iris japonica led to the isolation of four new aromatic glycosides. Their structures including the absolute configurations were determined by spectroscopic and chemical methods as (-)-4-hydroxy-3-methoxy acetophenone 4-O-ß-d-{6-O-[4-O-(7R,8S)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (1), (-)-4-hydroxy-3-methoxy acetophenone 4-O-ß-d-{6-O-[4-O-(7S,8R)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (2), (-)-4-hydroxy-3-methoxy acetophenone 4-O-ß-d-{6-O-[4-O-(7R,8R)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (3), (-)-4-hydroxy-3-methoxy acetophenone 4-O-ß-d-{6-O-[4-O-(7S,8S)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (4), respectively.

Nine new compounds from the whole plants of Rehmannia chingii.

Nine new compounds, together with 16 known analogs, were isolated from the whole plants of Rehmannia chingii. The structures of compounds 1-9 were elucidated on the basis of their spectroscopic data and chemical evidence. In addition, the new compounds were tested for their hepatoprotective activities against APAP-induced HepG2 cell damage and their ability to inhibit LPS-induced nitric oxide production in the murine microglia BV2 cell line. Compounds 2 and 5 exhibited pronounced hepatoprotective activities against APAP-induced HepG2 cell damage at a concentration of 10 µM, and compounds 4 and 9 showed moderate inhibitory activity against microglial inflammation factor with IC50 values of 3.51 and 7.11 µM, respectively.

Bioactive Iridoid Glycosides from the Whole Plants of Rehmannia chingii.

Nine new iridoid glycosides, rehmachingiiosides A-I (1-9), together with 16 known analogues, were isolated from the whole plants of Rehmannia chingii. The structures of compounds 1-9 were elucidated on the basis of spectroscopic data analysis and from chemical evidence. Furthermore, in two vitro assays, compounds 5 and 10 showed an inhibitory effect on LPS-induced NO production with IC50 values of 2.5 and 7.3 µM, and compounds 4, 6, and 10-12 (when evaluated at 10 µM) exhibited evidence of hepatoprotective effects against APAP-induced HepG2 cell damage.

Cytotoxic Lignans and Sesquiterpenoids from the Rhizomes of Acorus tatarinowii.

Five new compounds, including a rare phenyldihydronaphthalene lignanamide (1), an unusual hybrid-norlignan derivative (2), a rare cycloheptenone oxide derivative (3), one new acorane-type sesquiterpenoid (4), and one new guaiane-type sesquiterpenoid (5), together with seven known compounds (6-12), have been isolated from the rhizomes of Acorus tatarinowii. The structures of compounds 1-5 were determined by means of extensive spectroscopic methods. To the best of our knowledge, this is first report of a phenyldihydronaphthalene lignanamide and hybrid-norlignan and cycloheptenone oxide derivatives from the genus Acorus. In addition, compound 5 represents the first guaiane-type sesquiterpenoid with an epoxy group located between C-6 and C-9 from natural sources. Compounds 1-12 were evaluated for their in vitro cytotoxicity against five tumor cell lines. Among them, 2, 3, 5, and 10 exhibited moderate cytotoxicity with IC50 values of 2.11-9.23 µM.

Lignans from the rhizomes of Iris tectorum.

Chemical examination of the ethanol extract of rhizomes of Iris tectorum led to the isolation and characterization of three new lignans, (7R,7'R,8S,8'S)-5'-methoxy-neo-olivil (1a), (7S,7'S,8R,8'R) -5'-methoxy-neo-olivil (1b), (7S,7'R,8S,8'S)-neo-olivil (2a), (7R,7'S,8R,8'R)-neo-olivil (2b), (7R,7'R,8S,8'S,7''S,8''S)-threo-neo-olivil-4'-O-8-guaiacylglycerol ether (3), together with six known ones (4-9). Among them, compounds 1 and 2 were found to be racemic mixtures, respectively, which were verified by chiral HPLC analysis, compound 3 was a new sesquineolignan. The structures were elucidated on the basis of extensive spectroscopic analysis. To our knowledge, this is the first report of lignan constituents isolated from I. tectorum. All compounds were evaluated for their cytotoxicity against five human tumor cell lines and none of them displayed significant toxicity in tested cell lines at a concentration of 10 µM.

[Chemical constituents from Morus notabilis and their cytotoxic effect].

Une new flavonoids named as notabilisin K (1), together with four known compounds, morusin (2), mulberrofuran A (3), neocyclomorusin (4) and mornigrol F (5) are separated from 95% ethanol extracts of the twigs of Morus notabilis. Compounds 2-5 are separated from this plant for the first time. Notabilisin I, notabilisin J exhibits certain effect against cells of HCT-116, HepG2 and A2780 with IC50 values ranging from 1.47 µmol x L(-1) to 5.46 µmol x L(-1). Morusin exhibits strong effect against five kinds of human cancer cells (BGC823, A2780, HCT-116, HepG2 and NCI-H1650) with IC50 values ranging from 0.74 µmol x L(-1) to 1.58 µmol x L(-1).

[Flavonol glycosides from Lysimachia clethroides].

Eleven flavonol glycosides were isolated from the ethanol extract of Lysimachia clethroides by a combination of various chromatographic techniques including column chromatography over silica gel, Sephadex LH-20, and reversed-phase HPLC. Their structures were identified as astragalin (1), isoquercitrin (2), isorhamnetin-3-O-ß-D-glucopyranoside (3), quercetin-3-O-ß-D-6"-acetylglucopyranoside (4), quercetin-7-O-ß-D-glucopyranoside (5), prunin (6), 2-hydroxynaringin-5-O-ß-D-glucopyranoside (7), kaempferol-3-O-rutinonoside (8), kaempferol-3-O-robinobioside (9), rutin (10) and kaempferol-3,7-di-O-ß-D-glucopyranoside (11). Among them, compounds 4, 7 and 11 were obtained from the Lysimachia genus for the first time, while compounds 3, 5 and 9 were firstly reported from this plant. In the preliminary assays, compounds 2, 6 and 8 possessed significant inhibition against aldose reduc- tase, with IC50 values of 2.69, 1.00, 1.80 µmol · L(-1), respectively; none of compounds 1-11 exhibited obvious cytotoxic activity (IC50 > 10 µmol · L(-1)).

An unusual dihydrobenzofuroisocoumarin and ent-kaurane diterpenoids from Pteris multifida.

An unusual 5-C-methylated-dihydrobenzofuroisocoumarin, named multifidarin A (1), and two new ent-kaurane diterpenoids, named multikauranes A (2) and B (3), together with three known ent-kaurane diterpenoids, were isolated from the whole plants of Pteris multifida. The structures of 1-3 were elucidated by spectroscopic methods. The cytotoxic activities of all new compounds were evaluated against five human tumor cell lines. A possible biosynthetic process for the formation of 1 is proposed.

Simultaneous quantification of six major triterpenoid saponins in Schefflera kwangsiensis using high-performance liquid chromatography coupled to orbitrap mass spectrometry.

A simple and accurate analytical method was developed for simultaneous and quantitative analysis of six triterpenoid saponins in Schefflera kwangsiensis via high-performance liquid chromatography (HPLC) with mass spectrometry (MS) in this study. Separation was performed on a Thermo hypersil GOLD C18 column (150 mm × 2.1 mm, 5 µm). A mobile phase consisting of methanol/acetonitrile/8 mM ammonium acetate in water was used with a flow rate of 0.3 mL/min. The analytes were detected by MS with the electrospray ionisation (ESI) source combined with negative monitoring and full scan mode, and were analysed by extracted ion chromatography. This established HPLC-ESI-MS analysis demonstrated good linearity, sensitivity, stability, precision, accuracy and recovery. Therefore, this analytical method has great potential to be a novel tool to qualify S. kwangsiensis.

Cytotoxic taccalonolides and withanolides from Tacca chantrieri.

Six new taccalonolides, taccalonolides AT-AY (1-6), and two new withanolides, chantriolides D and E (7 and 8), together with ten known compounds (9-18), have been isolated from whole plants of Tacca chantrieri. The structures, including the absolute configurations of some of the compounds, were determined by spectroscopic and chemical methods. All compounds were evaluated for their in vitro cytotoxicity against five tumor cell lines. Compounds 9, 10, 13-15, and 17 exhibited cytotoxic activity, with IC50 values of 1.13-5.71 µM, while compound 7 showed selective cytotoxicity. The results indicated that taccalonolides with a six-membered lactone moiety located at C-15 and C-24 were devoid of cytotoxicity against five tumor cell lines (> 10 µM).

Two new Diels-Alder-type adducts from the stem barks of Morus yunanensis.

Two new Diels-Alder adducts, yunanensins B and D (1 and 2), were isolated from the stem bark of Morus yunanensis. Their structures were determined by spectroscopic analysis. Compounds 1 and 2 showed moderate antioxidant effects on liver microsomal lipid peroxidation induced by Fe(2+)-Cys system, with inhibitory ratios of 57.1% and 67.9% at a concentration of 10(-5) mol/l.

Iridal-type triterpenoids with neuroprotective activities from Iris tectorum.

Six novel iridal-type triterpenoids with a previously unreported 3,6-dihydro-2H-pyran moiety, named spirioiridotectals A-F (1-6), were isolated from the ethanol extract of the rhizomes of Iris tectorum. Their structures were elucidated on the basis of extensive spectroscopic analysis. Furthermore, in in vitro bioactivity assays, compounds 1, 2, and 6 exhibited neuroprotective activities against serum-deprivation-induced PC12 cell damage.